The US Department of Transportation has ordered an audit of the Boeing 737 MAX 8 certification process

The US Department of Transportation ordered Tuesday an audit of the Boeing 737 MAX 8 certification process, an aircraft that has had two fatal accidents in recent months.

Transport Secretary Elaine Chao's request highlights "compile a factual and objective history of the actions leading to the certification of the 737 MAX 8"said a statement, confirming the press information.

The Department of Justice has opened in as much, according to The Wall Street Journal, a criminal investigation into the development of this model, whose use has been suspended around the world.

"Safety is the number one priority of the ministry, and we are all saddened by the tragedies of the two recent Boeing 737 MAX 8 accidents in Indonesia and Ethiopia," Chao said.

An Ethiopian Airlines 737 MAX 8 crashed on 10 March southeast of Addis Ababa, killing 157 people on board. This was the second fatal accident in less than five months of the aircraft that entered service in May 2017, after Lion Air in Indonesia, which had 189 dead last October. Preliminary reports revealed similarities between the two accidents, during which the aircraft fell to the ground shortly after takeoff.

Until now, researchers have focused on the MCAS (Maneuverability Enhancement System) flight stabilization system involved in the accident in Indonesia.

Questions were raised about the certification of the aircraft, only part of which was examined, the 737 MAX being not a completely new aircraft, it was a question of improved variant of the 737 NG.

MCAS was developed for the MAX to compensate for its heavier engines.

The Federal Aviation Agency (FAA) is particularly under pressure for asking Boeing's own employees to inspect and approve this aircraft.

"Boeing requested a modification of this type of certification in January 2012 and the federal aviation agency granted it in March 2017," said Tuesday the Department of Transportation.

The audit has been entrusted to an independent institution, which will report its findings to the authorities.